HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 77/1/156    most recent biolreprod.106.055889v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Boiti, C. Articles by Zerani, M. Search for Related Content PubMed PubMed Citation Articles by Boiti, C. Articles by Zerani, M. Agricola Articles by Boiti, C. Articles by Zerani, M.

Vasoactive Peptides in the Luteolytic Process Activated by PGF2alpha in Pseudopregnant Rabbits at Different Luteal Stages¹

Dipartimento di Scienze Biopatologiche ed Igiene delle Produzioni Animali e Alimentari, Sezione di Fisiologia veterinaria, Laboratorio di Biotecnologie Fisiologiche,³ and Sezione di Anatomia Veterinaria,⁴ Università degli Studi di Perugia, I-06100 Perugia, Italy Dipartimento di Biologia Molecolare, Cellulare e Animale,⁵ Università degli Studi di Camerino I-62032 Camerino, Italy

ABSTRACT

To study the role of endothelial factors in luteal function, the dynamic profiles of genes for endothelin 1 (EDN1), its receptor subtypes, EDNRA and EDNRB, and angiotensin converting enzyme (ACE) were examined in corpora lutea (CL) obtained from rabbits on Days 4 and 9 of pseudopregnancy after prostaglandin (PG) F2 analogue (alfaprostol) treatment. The cell type distribution of EDN1 in the ovaries and its mechanisms of actions in vitro and in vivo were also studied. Positive immunostaining for EDN1 was localized in the luteal and endothelial cells, in granulosa cells of the follicles, and in the ovarian epithelium. The basal mRNA levels for EDNRA, EDNRB, and ACE were lower (P 0.01) in Day-4 CL than in Day-9 CL, whereas those for EDN1 did not differ between these two time-points. On Day 4, the luteal EDN1, EDNRA, EDNRB, and ACE mRNA levels were similarly increased two-fold (P 0.01) 1.5 h after alfaprostol injection, and did not show further changes in the subsequent 24 h. On Day 9, alfaprostol challenge transiently up-regulated (P 0.01) the luteal ACE transcripts at 1.5 h, and those of EDN1 at 1.5 h and 3 h, whereas the EDNRA and EDNRB transcript levels remained unchanged during the course of luteal regression. EDN1 decreased (P 0.01) progesterone release and increased (P 0.01) PGF2 secretion and NOS activity via the PLC/PKC pathway in Day-9 CL, but not in Day-4 CL, cultured in vitro. EDN1-induced, but not alfaprostol-induced luteolysis, was blocked by cotreatment in vivo with the ACE antagonist captopril. These findings support the hypothesis that PGF2 regulates luteolysis through intraluteal activation of the renin-angiotensin/EDN1 systems in CL that have acquired luteolytic competence.

ACE, corpus luteum function, EDN1, EDNRA, EDNRB, luteolysis, ovary

¹Supported by a grant from Ministero dell'Istruzione, dell'Università e della Ricerca (Contract no. 2005078028).

Correspondence: ²Cristiano Boiti, Dipartimento di Biopatologiche ed Igiene delle Produzioni Animali e Alimentari, Università of Perugia, S. Costanzo 4, 06126 Perugia, Italy. FAX: 39 075 5857654; e-mail: cristiano.boiti{at}unipg.it